JP2011113071A - Rotation detecting device, light source unit, and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotation detecting device that has a rotation-position detecting function for a rotation plate and a separation detecting function for detecting the separation of a member attached to the rotation plate, a light source unit equipped with the rotation detecting device, and a projector incorporating the light source unit. <P>SOLUTION: The projector includes, the light source unit, a display element, a projector control means, etc. The light source unit is composed of a blue light source device, a fluorescence device having the rotation plate of an approximately circular shape, on which a phosphor layer 102 that emits green wavelength band light is formed; a red light source device; a light source side optical system that condenses each color light onto a predetermined one surface; and the rotation detecting device 301. The rotation detecting device 301 has: the rotation plate with a notch formed in part of its periphery and with a fixing member provided in the notch; a position detecting portion provided in a range corresponding to the fixing member; a light emitting element for emitting light to the surface of the rotation plate, on which the position detecting portion is provided; and a light receiving element for detecting light reflected by the position detecting portion. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotation detection device, a light source unit including the rotation detection device, and a projector incorporating the light source unit.

  2. Description of the Related Art Today, data projectors are widely used as image projection apparatuses that project a screen of a personal computer, a video image, an image based on image data stored in a memory card or the like onto a screen. This projector focuses light emitted from a light source on a micromirror display element called a DMD (digital micromirror device) or a liquid crystal plate, and displays a color image on a screen.

  Conventionally, projectors using a high-intensity discharge lamp as the light source have been the mainstream of such projectors. However, in recent years, there have been many developments and proposals using light-emitting diodes, laser diodes, organic EL, phosphors, and the like as the light source. Has been made. For example, in Japanese Patent Application Laid-Open No. 2004-341105 (Patent Document 1), a disk-shaped transparent substrate provided with a phosphor layer that receives ultraviolet light as excitation light emitted from a solid light source and converts it into visible light. A light source unit having a fluorescent wheel and a solid-state light source has been proposed.

  The applicant of the present invention also includes a light source that emits blue wavelength band light as an excitation light source, and a phosphor layer that absorbs light emitted from the light source and converts the light into visible light such as red and green. The light source unit provided with the fluorescent wheel which has is proposed.

  The fluorescent wheel of the light source unit includes a light transmitting member that diffuses and transmits light from the blue light source in addition to the phosphor layer. Then, by irradiating the rotating fluorescent light wheel with blue light from the light source, each color such as red, green, and blue can be sequentially emitted from the fluorescent wheel.

  Here, the fluorescent wheel of the light source unit includes, for example, a phosphor layer that emits red light and green light on a substantially circular thin metal plate as a rotating plate, and a part of the rotating plate is cut away. And it can be set as the structure which adheres and fixes the light transmissive member which diffuses and permeate | transmits blue light to this notch part.

  However, when the fluorescent wheel is configured in this way, the metal substrate on which the phosphor layer is formed is firmly fixed to the rotating part, but the light transmitting member is a member having an arc that is about a semicircle or smaller than a semicircle. In addition, it is formed of a resin or glass and is fixed to the notch portion of the metal substrate only by adhesion. Therefore, there is a possibility that the light transmitting member bonded in this way may fall off due to deterioration over time, impact from outside, vibration, or the like. Therefore, it is necessary to provide a drop-off detecting means for detecting the drop-off of the light transmitting member and stopping the light source in the projector equipped with the fluorescent wheel.

  In addition, the projector is provided with a rotation detection device for detecting the rotation position of the rotating plate that emits light of each color such as red, green, and blue. As this rotation detection device, for example, as disclosed in Japanese Patent Application Laid-Open No. 2009-86609 (Patent Document 2), the light emitted from the light emitting element of the rotation detection device is irradiated to the rotation portion of the wheel motor, and the rotation portion is irradiated. There has been proposed a rotation detection device that detects a rotation position of a rotating plate by detecting reflected light from a formed position mark by a light receiving element of the rotation detection device.

JP 2004-341105 A JP 2009-86609 A

  Although the rotation detection device described in Patent Document 2 can detect the rotational position of the wheel, it cannot detect a dropout of an attachment member such as the light transmission member attached to the rotation plate. It was necessary to provide the detection means (drop-off detection means).

  The present invention has been made in view of the above-described problems of the prior art, and is capable of removing a fixed member such as a light transmitting member attached to the rotating plate together with a rotating position detecting function for detecting the rotating position of the rotating plate. An object of the present invention is to provide a rotation detection device having a drop-off detection function to detect, a light source unit including the rotation detection device, and a projector incorporating the light source unit.

  The rotation detection device of the present invention is provided with a substantially circular rotating plate in which a notch is formed in a part of the outer periphery and a fixing member is provided in the notch, and in a range corresponding to the fixing member. And a light receiving element for irradiating light on a surface of the rotating plate on which the position detecting unit is provided, and a light receiving element for detecting light reflected by the position detecting unit.

  The fixing member provided in the notch is a light transmitting member having translucency and diffusibility.

  Further, in this rotation detection device, a phosphor layer that receives excitation light and emits light in a predetermined wavelength region is formed in a range excluding the notch portion of the rotation plate.

  And the said position detection part is formed on the surface on the opposite side to the surface in which the said fluorescent substance layer is formed within the formation range of the said light transmissive member.

  This position detection part may be formed over the entire formation range of the light transmission member.

  The position detection unit is a dichroic layer that transmits excitation light that excites the phosphor and reflects light emitted from the light emitting element.

  The rotation detection device includes a light absorption layer that absorbs light emitted from the light emitting element on a surface opposite to the surface on which the phosphor layer is formed, within the formation range of the phosphor layer. Is formed.

  The light source unit of the present invention includes a blue light source device that emits excitation light in a blue wavelength band, a light source side optical system that condenses light emitted from the rotating plate on a predetermined surface, a rotation detection device, The rotation detection device is any one of the rotation detection devices described above, and the phosphor layer formed on the rotation plate receives at least the blue wavelength band excitation light and emits light in the green wavelength band. It is a fluorescent substance layer which emits.

  In addition, the rotating plate may be formed with a phosphor layer that emits green wavelength band light and a phosphor layer that emits red wavelength band light upon receiving excitation light in the blue wavelength band.

  The light source unit of the present invention includes a red light source device that emits light in a red wavelength band, blue band light that diffuses and transmits through the light transmitting member attached to the rotating plate, and a phosphor layer formed on the rotating plate. And a light source side optical system that condenses the red band light emitted from the red light source device and the red band light emitted from the red light source device on a predetermined surface.

  The projector of the present invention includes any one of the light source units described above, a display element, a light guide optical system that guides light from the light source unit to the display element, and an image emitted from the display element. A projection-side optical system for projecting onto a screen, and projector control means for controlling the light source unit and the display element are provided.

  According to the present invention, a rotation detection device having a drop-off detection function for detecting a drop-off of a fixed member such as a light transmitting member attached to the rotation plate as well as a rotation position detection function for detecting the rotation position of the rotation plate, and the rotation detection It is possible to provide a light source unit including the device and a projector incorporating the light source unit.

It is an external appearance perspective view which shows the projector provided with the light source unit which concerns on the Example of this invention. It is a figure which shows the functional circuit block of the projector provided with the light source unit which concerns on the Example of this invention. 1 is a schematic plan view showing an internal structure of a projector provided with a light source unit according to an embodiment of the present invention. It is a figure which shows the rotation detection apparatus containing the fluorescence wheel which concerns on the Example of this invention. It is a figure which shows the rotation detection apparatus containing the fluorescence wheel which concerns on the Example of this invention. It is the front schematic diagram of the fluorescent wheel which concerns on the Example of this invention, and the plane schematic diagram which shows a partial cross section. It is a back surface schematic diagram of the fluorescent wheel which concerns on the Example of this invention.

  Hereinafter, modes for carrying out the present invention will be described. The projector 10 includes a light source unit 60, a display element 51, a light guide optical system 170 that guides light from the light source unit 60 to the display element 51, and a projection side that projects an image emitted from the display element 51 onto a screen. An optical system 220 and projector control means for controlling the light source unit 60 and the display element 51 are provided.

  The light source unit 60 includes a blue light source device 70, a fluorescent light emitting device 100 having a fluorescent wheel 101 whose rotation is controlled, a red light source device 120, a rotation detecting device 301, and a light source side optical system 140. . The blue light source device 70 irradiates the phosphor layer 102 laid on the fluorescent wheel 101 of the fluorescent light emitting device 100 with excitation light in the blue wavelength band. The fluorescent wheel 101 is formed with a phosphor layer 102 that receives excitation light and emits light in the green wavelength band on the wheel surface. Further, a light transmitting member 105 that diffuses and transmits light is attached to the fluorescent wheel 101 by adhesion. The fluorescent wheel 101 is a rotating plate that is rotated by a wheel motor 110 controlled by the projector control means.

  Specifically, the fluorescent wheel 101 is a substantially circular thin metal plate, and a notch is formed in a part of the outer periphery. Then, a light transmitting member 105 having translucency and diffusibility is bonded and fixed as a fixing member so as to cover the notch. The light transmitting member 105 has one surface blasted or the like, and converts incident light having high directivity into light having low directivity. Further, in this fluorescent wheel 101, a band-shaped phosphor layer 102 containing a phosphor that is excited by receiving light in the blue wavelength band and emits light in the green wavelength band is in a range excluding the notch, The fluorescent wheel 101 is formed in the circumferential direction in the vicinity of the outer peripheral portion.

  That is, when blue light with high directivity from the blue light source device 70 is irradiated onto the rotating fluorescent wheel 101, blue light and green light with low directivity are emitted from the fluorescent wheel 101.

  The red light source device 120 includes a red light source 121 that is a light emitting diode that emits light in a red wavelength band. In this way, by providing the red light source device 120 individually without providing the phosphor wheel 101 with the red phosphor layer having a lower luminous efficiency than the green phosphor, the green phosphor layer having a relatively high luminous efficiency can be obtained. The brightness of the screen can be improved by obtaining the green light and the red light suitable for the amount of blue light diffusely transmitted through the light transmitting member 105 of the fluorescent wheel 101.

  The light source side optical system 140 includes a dichroic mirror that is disposed between the blue light source device 70 and the fluorescent light emitting device 100 and transmits excitation light and reflects fluorescent light from the fluorescent material. The light source side optical system 140 includes a blue band light diffused and transmitted through the light transmitting member 105 of the fluorescent wheel 101, a green band light reflected by the dichroic mirror, and a red band emitted from the red light source 121 of the red light source device 120. A plurality of reflecting mirrors and dichroic mirrors for condensing light at the entrance of the light tunnel 175, which is a predetermined surface, and a condensing lens.

  That is, the light source control means in the projector control means individually controls the light emission of the blue light source device 70 and the red light source device 120, thereby emitting light source light in the red, green, and blue wavelength bands sequentially from the light source unit 60. be able to. Then, the DMD that is the display element 51 of the projector 10 displays the light of each color in a time-sharing manner according to the data, so that a color image can be generated on the screen.

  The rotation detecting device 301 includes a fluorescent wheel 101 as a rotating plate, a light emitting element, a light receiving element, and a detection circuit. The light emitting element irradiates the fluorescent wheel 101 with light in the infrared region (infrared rays) as detection light. The light receiving element detects infrared light as detection light reflected by a position detection unit provided on a light transmission member 105 bonded and fixed to the fluorescent wheel 101.

  This position detection unit is provided in a predetermined range corresponding to the light transmission member 105 within the range of formation of the light transmission member 105 in the fluorescent wheel 101. Specifically, the position detection unit is coated on the entire surface on the opposite side of the surface on which the phosphor layer 102 is formed and on the opposite side of the light transmission member 105 from the blasted surface. It is a dichroic layer 106. The dichroic layer 106 transmits blue band light emitted from the blue light source device 70 and reflects other light including infrared rays emitted from the light emitting element. In addition, the detection light emitted from the light emitting element of the rotation detecting device 301 is irradiated on the surface of the fluorescent wheel 101 opposite to the surface on which the fluorescent material layer 102 is formed within the formation range of the fluorescent material layer 102. Absorbing light absorption layer 107 is formed. The light absorption layer 107 is a black coating portion to which a black paint is applied.

  That is, when the detection light emitted from the light emitting element is applied to the surface of the fluorescent wheel 101 on which the dichroic layer 106 as the position detection unit is provided, the detection light is transmitted through the rotating fluorescent wheel 101. The light receiving element detects reflected light only when the dichroic layer 106 and the light absorption layer 107 of the member 105 are sequentially irradiated and infrared rays are irradiated on the dichroic layer 106 serving as a position detection unit. Then, the detection circuit transmits the electrical signal photoelectrically converted by the light receiving element to the projector control means. Thereby, the rotation detection device 301 can detect the rotation position of the fluorescent wheel 101 that rotates at a predetermined rotation speed. In addition, when the light transmission member 105 is dropped from the fluorescent wheel 101, the reflected light is not detected by the light receiving element. Therefore, the rotation detection device 301 can detect the drop of the light transmission member 105 from the fluorescent wheel 101. Can do.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an external perspective view of the projector 10. In this embodiment, left and right in the projector 10 indicate the left and right direction with respect to the projection direction, and front and rear indicate the screen side direction of the projector 10 and the front and rear direction with respect to the traveling direction of the light beam.

  As shown in FIG. 1, the projector 10 has a substantially rectangular parallelepiped shape, and has a lens cover 19 that covers the projection port on the side of the front panel 12 that is a front side plate of the projector housing. The panel 12 is provided with a plurality of intake holes 18. Further, although not shown, an Ir receiver for receiving a control signal from the remote controller is provided.

  In addition, a key / indicator unit 37 is provided on the top panel 11 of the housing. The key / indicator unit 37 switches a power switch key, a power indicator for notifying power on / off, and switching on / off of projection. Keys and indicators such as an overheat indicator for notifying when a projection switch key, a light source unit, a display element, a control circuit, etc. are overheated are arranged.

  In addition, on the rear surface of the housing, there are provided various terminals 20 such as an input / output connector section and a power adapter plug that provide a USB terminal, a D-SUB terminal for image signal input, an S terminal, an RCA terminal, etc. on the rear panel. Yes. A plurality of intake holes 18 are formed in the back panel. A plurality of exhaust holes 17 are formed in each of the right panel, which is a side plate of the housing (not shown), and the left panel 15, which is the side plate shown in FIG.

  Next, projector control means of the projector 10 will be described with reference to the block diagram of FIG. The projector control means includes a control unit 38, an input / output interface 22, an image conversion unit 23, a display encoder 24, a display drive unit 26, and the like. Image signals of various standards input from the input / output connector unit 21 are input / output. The image conversion unit 23 converts the image signal into a predetermined format suitable for display via the interface 22 and the system bus (SB), and outputs the image signal to the display encoder 24.

  The display encoder 24 develops and stores the input image signal in the video RAM 25, generates a video signal from the stored contents of the video RAM 25, and outputs the video signal to the display drive unit 26.

  The display drive unit 26 functions as display element control means, and drives the display element 51, which is a spatial light modulation element (SOM), at an appropriate frame rate corresponding to the image signal output from the display encoder 24. The light beam emitted from the light source unit 60 is irradiated onto the display element 51 through the light guide optical system, thereby forming an optical image with the reflected light of the display element 51, and a projection side optical system to be described later The image is projected and displayed on a screen (not shown). The movable lens group 235 of the projection side optical system is driven by the lens motor 45 for zoom adjustment and focus adjustment.

  The image compression / decompression unit 31 performs a recording process in which the luminance signal and the color difference signal of the image signal are data-compressed by a process such as ADCT and Huffman coding, and sequentially written in a memory card 32 that is a detachable recording medium. Further, the image compression / decompression unit 31 reads the image data recorded on the memory card 32 in the reproduction mode, decompresses individual image data constituting a series of moving images in units of one frame, and converts the image data into the image conversion unit 23. Is output to the display encoder 24 and the processing for enabling the display of a moving image or the like based on the image data stored in the memory card 32 is performed.

  The control unit 38 controls operation of each circuit in the projector 10, and includes a ROM that stores operation programs such as a CPU and various settings fixedly, and a RAM that is used as a work memory. .

  An operation signal of a key / indicator unit 37 composed of a main key and an indicator provided on the top panel 11 of the housing is directly sent to the control unit 38, and a key operation signal from the remote controller is sent to the Ir receiving unit 35. , And the code signal demodulated by the Ir processor 36 is output to the controller 38.

  Note that an audio processing unit 47 is connected to the control unit 38 via a system bus (SB). The sound processing unit 47 includes a sound source circuit such as a PCM sound source, converts the sound data into analog in the projection mode and the playback mode, and drives the speaker 48 to emit loud sounds.

  Further, the control unit 38 controls a light source control circuit 41 as a light source control unit, and the light source control circuit 41 is configured so that light source light of a predetermined wavelength band required at the time of image generation is emitted from the light source unit 60. In addition, the light emission of the blue light source device and the red light source device of the light source unit 60 is individually controlled.

  Further, the control unit 38 causes the cooling fan drive control circuit 43 to perform temperature detection using a plurality of temperature sensors provided in the light source unit 60 and the like, and controls the rotation speed of the cooling fan from the result of the temperature detection. Further, the control unit 38 causes the cooling fan drive control circuit 43 to keep the cooling fan rotating even after the projector body is turned off by a timer or the like, or to turn off the projector body depending on the result of temperature detection by the temperature sensor. Control is also performed.

  Next, the internal structure of the projector 10 will be described. FIG. 3 is a schematic plan view showing the internal structure of the projector 10. As shown in FIG. 3, the projector 10 includes a control circuit board 241 in the vicinity of the right panel 14. The control circuit board 241 includes a power circuit block, a light source control block, and the like. In addition, the projector 10 includes a light source unit 60 on the side of the control circuit board 241, that is, at a substantially central portion of the projector housing. Further, the projector 10 includes an optical system unit 160 between the light source unit 60 and the left panel 15.

  The light source unit 60 includes a blue light source device 70 disposed in the vicinity of the rear panel 13 at a substantially central portion in the left-right direction of the projector housing, and an optical axis of a light beam emitted from the blue light source device 70. A fluorescent light emitting device 100 disposed in the vicinity of the front panel 12, a red light source device 120 disposed between the blue light source device 70 and the fluorescent light emitting device 100, light emitted from the fluorescent light emitting device 100, and a red light source device 120 The light source side optical system 140 that condenses each color light to the entrance of the light tunnel 175, which is a predetermined surface, and converts the optical axis of the light emitted from the light source to the same optical axis, and the fluorescence of the fluorescent light emitting device 100 And a rotation detection device 301 that irradiates the wheel 101 with infrared rays.

  The blue light source device 70 includes a blue light source 71 disposed so that its optical axis is parallel to the back panel 13, and a reflection mirror group 75 that converts the optical axis of light emitted from the blue light source 71 by 90 degrees in the direction of the front panel 12. A condensing lens 78 that condenses the light emitted from the blue light source 71 reflected by the reflecting mirror group 75, and a heat sink 81 disposed between the blue light source 71 and the right panel 14.

  The blue light source 71 includes a plurality of blue laser diodes arranged in a matrix, and a collimator lens 73 that converts light emitted from each blue laser diode into parallel light is disposed on the optical axis of each blue laser diode. ing. The reflection mirror group 75 includes a plurality of reflection mirrors arranged in a stepped manner, and reduces the cross-sectional area of the light beam emitted from the blue light source 71 in one direction and emits the light to the condenser lens 78.

  A cooling fan 261 is disposed between the heat sink 81 and the back panel 13, and the blue light source 71 is cooled by the cooling fan 261 and the heat sink 81. Further, a cooling fan 261 is also disposed between the reflection mirror group 75 and the back panel 13, and the reflection mirror group 75 and the condenser lens 78 are cooled by the cooling fan 261.

  Fluorescent light emitting device 100 is arranged to be parallel to front panel 12, that is, fluorescent wheel 101 arranged so as to be orthogonal to the optical axis of light emitted from blue light source device 70, and rotationally drives this fluorescent wheel 101 A wheel motor 110, a condensing lens group 111 that condenses the light bundle emitted from the fluorescent wheel 101 toward the rear panel 13, and a light condensing that collects the light bundle emitted from the fluorescent wheel 101 toward the front panel 12. A lens 115.

  The fluorescent wheel 101 absorbs the light emitted from the blue light source device 70 as excitation light and emits the fluorescent light emitted in the green wavelength band, and transmits light that diffuses and transmits the light emitted from the blue light source device 70. And a member. The surface on the back panel 13 side of the base material of the fluorescent wheel 101 on which the green phosphor layer is disposed is mirror-processed by silver vapor deposition or the like. Furthermore, fine irregularities are formed on the surface of the fluorescent wheel 101 in the light transmitting member by sandblasting or the like.

  The light emitted from the blue light source device 70 irradiated on the green phosphor layer of the phosphor wheel 101 excites the green phosphor in the green phosphor layer, and the light bundle emitted in all directions from the green phosphor is The light is directly reflected to the rear panel 13 side or reflected from the surface of the fluorescent wheel 101 and then emitted to the rear panel 13 side and enters the condenser lens group 111. Further, the light emitted from the blue light source device 70 irradiated on the light transmitting member of the fluorescent wheel 101 is incident on the condenser lens 115 as diffuse transmitted light diffused by the fine unevenness. A cooling fan 261 is disposed between the wheel motor 110 and the front panel 12, and the fluorescent wheel 101 is cooled by the cooling fan 261. A specific configuration of the fluorescent wheel 101 will be described later together with the rotation detection device 301.

  The red light source device 120 includes a red light source 121 arranged so that the optical axis is parallel to the blue light source 71, and a condensing lens group 125 that condenses the light emitted from the red light source 121. The red light source device 120 is arranged so that the light axis from the blue light source device 70 and the green wavelength band light emitted from the fluorescent wheel 101 intersect the optical axis. The red light source 121 is a red light emitting diode. Furthermore, the red light source device 120 includes a heat sink 130 disposed on the right panel 14 side of the red light source 121. A cooling fan 261 is disposed between the heat sink 130 and the front panel 12, and the red light source 121 is cooled by the cooling fan 261.

  The light source side optical system 140 includes a condenser lens that collects the light bundles in the red, green, and blue wavelength bands, and a reflection mirror that converts the optical axes of the light bundles in the respective color wavelength bands into the same optical axis, It consists of a dichroic mirror. Specifically, at the position where the blue wavelength band light emitted from the blue light source device 70 and the green wavelength band light emitted from the fluorescent wheel 101 and the red wavelength band light emitted from the red light source device 120 intersect, A first dichroic mirror 141 that transmits blue and red wavelength band light, reflects green wavelength band light, and converts the optical axis of the green light by 90 degrees toward the left panel 15 is disposed.

  Also, on the optical axis of the blue wavelength band light diffusely transmitted through the fluorescent wheel 101, that is, between the condenser lens 115 and the front panel 12, the blue wavelength band light is reflected and the optical axis of this blue light is on the left side. A first reflecting mirror 143 that converts 90 degrees in the direction of the panel 15 is disposed. Further, on the optical axis of the blue wavelength band light reflected by the first reflection mirror 143 and in the vicinity of the optical system unit 160, a second reflection mirror for converting the optical axis of the blue light by 90 degrees in the direction of the back panel 13 145 is arranged.

  Further, the optical axis of the red wavelength band light transmitted through the first dichroic mirror 141, the optical axis of the green wavelength band light reflected by the first dichroic mirror 141 so as to coincide with this optical axis, and the second reflection mirror 145 At the position where the optical axis of the reflected blue wavelength band light intersects, the blue wavelength band light is transmitted, the red and green wavelength band light is reflected, and the optical axes of the red and green light are 90 degrees toward the rear panel 13. A second dichroic mirror 148 for changing the degree is arranged. A condensing lens is disposed between the dichroic mirror and the reflecting mirror.

  By configuring the light source side optical system 140 in this way, when the fluorescent wheel 101 is rotated and light is emitted from the blue light source device 70 and the red light source device 120 at different timings, red, green, and blue wavelength band lights are emitted from the light source. By sequentially entering the light tunnel 175 via the side optical system 140 and the DMD that is the display element 51 of the projector 10 displaying each color light in a time-sharing manner according to the data, a color image can be generated on the screen. .

  The optical system unit 160 includes an illumination side block 161 located on the left side of the blue light source device 70, an image generation block 165 located near the position where the back panel 13 and the left panel 15 intersect, and the light source side optical system 140. And the projection side block 168 located between the left side panel 15 and the left side panel 15 are formed in a substantially U-shape.

  The illumination side block 161 includes a part of a light guide optical system 170 that guides the light source light emitted from the light source unit 60 to the display element 51 provided in the image generation block 165. The light guide optical system 170 included in the illumination-side block 161 includes a light tunnel 175 that uses a light beam emitted from the light source unit 60 as a light beam having a uniform intensity distribution, and collects light source light on an incident surface of the light tunnel 175. A condensing lens 173 that emits light, a condensing lens 178 that condenses the light emitted from the light tunnel 175, and an optical axis conversion mirror 181 that converts the optical axis of the light bundle emitted from the light tunnel 175 in the direction of the image generation block 165. Etc.

  As the light guide optical system 170, the image generation block 165 includes a condensing lens 183 that condenses the light source light reflected by the optical axis conversion mirror 181 on the display element 51, and a light beam that has passed through the condensing lens 183 as a display element. And an irradiation mirror 185 that irradiates 51 at a predetermined angle. Further, the image generation block 165 includes a DMD serving as the display element 51, and a heat sink 190 for cooling the display element 51 is disposed between the display element 51 and the rear panel 13. Element 51 is cooled. Further, a condensing lens 195 as the projection-side optical system 220 is disposed in the vicinity of the front surface of the display element 51.

  The projection-side block 168 has a lens group of the projection-side optical system 220 that emits ON light reflected by the display element 51 to the screen. The projection-side optical system 220 includes a fixed lens group 225 built in a fixed lens barrel and a movable lens group 235 built in a movable lens barrel, and is a variable focus lens having a zoom function, and is movable by a lens motor. Zoom adjustment and focus adjustment can be performed by moving the lens group 235.

  Specific configurations of the fluorescent light emitting device 100 and the rotation detecting device 301 will be described with reference to FIGS. 4 is a view showing a rotation detection device 301 including the fluorescent wheel 101 of the fluorescent light emitting device 100, and FIG. 5 is a view showing the rotation detection device 301 including the fluorescent wheel 101 in a state where the light transmitting member 105 is separated. is there. FIGS. 6A, 6B, and 7 are a schematic front view, a schematic plan view showing a partial cross section, and a schematic back view of the fluorescent wheel 101. FIG.

  As shown in the figure, the fluorescent wheel 101 is a substantially circular thin metal substrate, and a circular opening for fitting the shaft of the wheel motor 110 to the center of the substrate, and the fluorescent wheel 101 in the vicinity of the circular opening. A pair of holes formed at positions symmetrical to each other with respect to the rotation center. The fluorescent wheel 101 has a motor shaft inserted into a circular opening in the center, and a convex portion provided on a disk-shaped motor hub is fitted in a hole near the circular opening, so that the wheel motor It is firmly fixed to 110 rotating parts. That is, the fluorescent wheel 101 is a rotating plate that is rotated by the wheel motor 110 controlled by the projector control means.

  Further, a light transmitting member 105 is attached to the fluorescent wheel 101. Specifically, an arc-shaped notch is formed in a part of the outer periphery of the metal base, and the light transmitting member 105 as a fixing member is bonded and fixed so as to cover the notch.

  The light transmitting member 105 has an arc shape and is made of light transmitting glass or resin. And the notch part (opening) formed in a metal base material is made into circular arc shape smaller than the light transmissive member 105 provided in a notch part. In addition, the base material on the end side of the arc-shaped notch is formed in steps so that the adhesive surface 117 on which both ends of the light transmitting member 105 are arranged is thin relative to the center side of the base material. Is done. Further, the base material on the rotation center side of the arc-shaped notch is formed so that the arc-shaped surface on which the portion near the inner periphery of the arc-shaped light transmitting member 105 is arranged is flush with the adhesive surface 117. The That is, the arc-shaped surface on the rotation center side of the bonding surface 117 and the cutout portion is a thin-walled concave portion as compared with other metal substrate portions.

  Further, the light transmission member 105 is formed in an arc shape having a step corresponding to the notch and the recess of the metal substrate. Then, both surfaces of the light transmitting member 105 after being attached to the metal substrate are flush with both surfaces of the metal substrate, that is, the surface of the metal substrate and the surface of the light transmitting member 105 are flat. In addition, the light transmitting member 105 is mounted so as to be fitted into the notch and the recess of the metal base, and both ends of the light transmitting member 105 are fixed by the adhesive 118 on the bonding surface 117.

  In addition, this fluorescent wheel 101 has an arc-shaped opening 109 corresponding to the amount of mass reduction on the notch portion side by providing a notch portion and mounting the light transmitting member 105 for adjusting the mass balance. It is provided at a position that is 180 degrees symmetrical with respect to the notch. As a result, the center of gravity of the fluorescent wheel 101 can be made to coincide with the center of rotation, so that the fluorescent wheel 101 rotates without being decentered and is effective due to the deviation of the irradiation position of the blue light from the blue light source device 70. It is possible to prevent performance degradation such as light reduction.

  As shown in FIG. 6B, the light transmitting member 105 is subjected to blasting or the like on the surface on the blue light source 71 side, and directs light with high directivity emitted from the blue light source 71. Convert to low light. That is, the light transmission member 105 has diffusibility. Further, on the surface of the fluorescent wheel 101 on the blue light source 71 side, a band-shaped phosphor layer 102 containing a phosphor that emits green wavelength band light when excited by receiving light in the blue wavelength band includes the fluorescent wheel. It is a range excluding the notch portion of 101 and is formed in the circumferential direction in the vicinity of the outer peripheral portion of the fluorescent wheel 101. Therefore, the fluorescent wheel 101 having the light transmitting member 105 receives blue light with high directivity from the blue light source 71 when rotating by the wheel motor 110, and thereby blue light (diffusion from the light transmitting member 105). It functions as a light emitting plate that emits transmitted light) and green light (light emitted from the phosphor).

  The rotation detection device 301 includes a fluorescent wheel 101 that is a rotating plate, a light emitting element, a light receiving element, and a detection circuit. The light emitting element irradiates light in the infrared region (infrared rays) as detection light near the outer periphery of the rotating fluorescent wheel 101. The light receiving element detects infrared light as detection light reflected by a position detection unit provided on a light transmission member 105 bonded and fixed to the fluorescent wheel 101.

  This position detector is provided in a predetermined range within the formation range of the light transmitting member 105 as a range corresponding to the light transmitting member 105 in the fluorescent wheel 101. Specifically, this position detection unit is on the surface opposite to the surface on which the phosphor layer 102 is formed, and is the surface of the light transmitting member 105 opposite to the blasted surface, that is, the rotation detection device. This is a dichroic layer 106 coated over the entire surface of the light transmitting member 105, which is one surface on the 301 side. The dichroic layer 106 transmits blue band light emitted from the blue light source device 70 and reflects other light including infrared rays emitted from the light emitting element. Then, the detection light (from the light emitting element of the rotation detecting device 301) is irradiated on the surface of the fluorescent wheel 101 opposite to the surface on which the fluorescent material layer 102 is formed within the formation range of the fluorescent material layer 102 ( A light absorption layer 107 that absorbs infrared rays is formed. The light absorption layer 107 is a black coating portion to which a black paint is applied.

  That is, when the detection light emitted from the light emitting element is applied to the surface of the fluorescent wheel 101 on which the dichroic layer 106 as the position detection unit is provided, the detection light is transmitted through the rotating fluorescent wheel 101. The light receiving element detects reflected light only when the dichroic layer 106 and the light absorption layer 107 of the member 105 are sequentially irradiated and infrared rays are irradiated on the dichroic layer 106 serving as a position detection unit. Then, the detection circuit transmits the electrical signal photoelectrically converted by the light receiving element to the projector control means. Thereby, the rotation detection device 301 can detect the rotation position of the fluorescent wheel 101 that rotates at a predetermined rotation speed. In addition, when the light transmission member 105 is dropped from the fluorescent wheel 101, the reflected light is not detected by the light receiving element. Therefore, the rotation detection device 301 can detect the drop of the light transmission member 105 from the fluorescent wheel 101. Can do.

  The position detection unit can be formed as a dichroic layer 106 having various shapes such as dots and lines (lines formed radially from the rotation center) in a range corresponding to the light transmitting member 105. Thereby, when the light for detection emitted from the light emitting element is irradiated to the light absorption layer 107 formed on the surface of the metal base material, the light is absorbed by the light absorption layer 107, and the dichroic layer 106 of the light transmitting member 105 is absorbed. Transmits when it is irradiated to other parts. That is, the detection light emitted from the light emitting element is reflected only when it is applied to the dot-like or linear dichroic layer 106 (position detection unit) provided on the light transmission member 105. Therefore, by providing the position detection unit on the light transmission member 105, the rotation detection device 301 can detect the rotation position of the fluorescent wheel 101 and also detect the drop of the light transmission member 105.

  In addition, if the dichroic layer 106 is formed by coating as a position detection unit in a range corresponding to the entire formation range of the light transmission member 105 in the fluorescent wheel 101, position detection is performed at the front end or the rear end of the light transmission member 105 in the rotation direction. On the other hand, it is preferable that the light transmission member 105 can be detected by detecting the entire light transmission member 105, such as dropping or chipping.

  Thus, according to the present invention, it is possible to provide a rotation detection device 301 having a rotation position detection function for detecting the rotation position of the rotation plate and a drop detection function for detecting the drop of the light transmission member 105 attached to the rotation plate. Can do. Furthermore, it is possible to provide the light source unit 60 having a simple configuration including the rotation detection device 301 and the projector 10 incorporating the light source unit 60 and realizing safety and cost reduction.

  The type of light source employed in the light source unit 60 and the configuration of the fluorescent wheel 101 are not limited to the above-described embodiments. For example, the red light source 121 may be replaced with a light emitting diode, and a laser light emitter may be employed. As described above, by using a light emitting diode for the red light source 121, the product cost can be reduced while the red light source has a high luminance.

  Further, the phosphor layer 102 formed on the base material of the fluorescent wheel 101 is not limited to the case where only one kind is provided, and the phosphor layer 102 emitting red wavelength band light may be provided together. Alternatively, a phosphor layer 102 that emits a wavelength band of a complementary color such as yellow may be provided.

  When the red phosphor layer 102 is formed on the phosphor wheel 101 together with the green phosphor layer 102, the phosphor wheel 101 includes a light transmitting member 105 that diffuses and transmits the excitation light in the blue band, and a blue wavelength. It has a green phosphor layer 102 that emits green wavelength band light upon receiving excitation light in a band, and a red phosphor layer 102 that emits red wavelength band light upon receiving excitation light in a blue wavelength band. Accordingly, the light source unit 60 in which the red light source device 120 is omitted can be incorporated in the projector 10. In this case, the first dichroic mirror 141 and the second dichroic mirror 148 in the light source side optical system 140 are dichroic mirrors that reflect green and red light and transmit blue light, and are emitted from the fluorescent wheel 101. The optical path of the red fluorescent light is the same as that of the green fluorescent light, and the red light can also enter the entrance of the light tunnel 175.

  The light source control means may be provided individually in the light source unit 60 without being provided in the projector 10. Further, the layout of each optical component is not limited to the above-described configuration (see FIG. 3), and various layouts can be adopted. For example, when the base material on which the phosphor layer 102 is disposed is formed of a transparent base material that transmits light, the light source side optical system 140 is located at a position where the optical axis of the blue light source 71 and the optical axis of the red light source 121 intersect. In addition, the light from the fluorescent light wheel 101 arranged on the optical axis of the blue light source 71 and disposed between the blue light source device 70 and the red light source device 120 is transmitted and the light from the red light source 121 is reflected, or A dichroic mirror that reflects light from the fluorescent wheel 101 and transmits light from the red light source 121 is arranged. Even when the fluorescent wheel 101 and the light source side optical system 140 are employed, the same effects as described above can be obtained.

  In the light source side optical system 140, in the above-described example, the dichroic mirror is used to select the conversion in the optical axis direction and the transmission and reflection according to the wavelength. The above-described dichroic mirror may be replaced with other alternative means.

  And this invention is not limited to the above Example, A change and improvement are possible freely in the range which does not deviate from the summary of invention. For example, the member fixed to the rotating plate is not limited to the light transmitting member 105, and is not limited to the case where the member is fixed by adhesion such as fixing by clamping.

10 Projector
11 Top panel 12 Front panel
13 Rear panel 14 Right panel
15 Left panel 17 Exhaust hole
18 Air intake hole 19 Lens cover
20 Various terminals 21 Input / output connector
22 I / O interface 23 Image converter
24 Display encoder 25 Video RAM
26 Display drive unit 31 Image compression / decompression unit
32 Memory card 35 Ir receiver
36 Ir processing section 37 Key / indicator section
38 Control unit 41 Light source control circuit
43 Cooling fan drive control circuit 45 Lens motor
47 Audio processor 48 Speaker
51 Display element
60 Light source unit 70 Blue light source device
71 Blue light source 73 Collimator lens
75 Reflective mirror group 78 Condensing lens
81 Heat sink 100 Fluorescent light emitting device
101 Fluorescent wheel 102 Phosphor layer
105 Light transmission member 106 Dichroic layer
107 Light absorption layer
109 opening 110 wheel motor
111 Condensing lens group 115 Condensing lens
117 Adhesive surface 118 Adhesive
120 Red light source 121 Red light source
125 condenser lens group 130 heat sink
140 Light source side optical system 141 First dichroic mirror
143 First reflection mirror 145 Second reflection mirror
148 Second dichroic mirror 160 Optical system unit
161 Lighting block 165 Image generation block
168 Projection side block 170 Light guiding optical system
173 Condensing lens 175 Light tunnel
178 Condensing lens 181 Optical axis conversion mirror
183 Condensing lens 185 Irradiation mirror
190 Heat sink 195 Condenser lens
220 Projection-side optical system 225 Fixed lens group
235 Movable lens group
241 Control circuit board 261 Cooling fan
301 Rotation detector

Claims (11)

A notch part is formed in a part of the outer periphery, and a substantially circular rotating plate provided with a fixing member in the notch part,
A position detector provided in a range corresponding to the fixing member;
A light emitting element that irradiates light to a surface on which the position detection unit of the rotating plate is provided;
A light receiving element for detecting light reflected by the position detection unit;
A rotation detection device comprising:   The rotation detecting device according to claim 1, wherein the fixing member provided in the notch is a light transmissive member having translucency and diffusibility.   3. The rotation detection device according to claim 1, wherein a phosphor layer that receives excitation light and emits light in a predetermined wavelength region is formed in a range excluding the notch portion of the rotating plate.   4. The rotation detection according to claim 3, wherein the position detection unit is formed on a surface opposite to a surface on which the phosphor layer is formed within a range in which the light transmission member is formed. apparatus.   The rotation detection device according to claim 4, wherein the position detection unit is formed over the entire formation range of the light transmission member.   The said position detection part is a dichroic layer which permeate | transmits the excitation light which excites the said fluorescent substance, and reflects the light irradiated from the said light emitting element, The Claim 3 thru | or 5 characterized by the above-mentioned. Rotation detection device.   A light absorption layer that absorbs light emitted from the light emitting element is formed on the surface opposite to the surface on which the phosphor layer is formed within the formation range of the phosphor layer. The rotation detection device according to any one of claims 3 to 6. A blue light source device that emits excitation light in a blue wavelength band;
A light source side optical system for condensing light emitted from the rotating plate on a predetermined surface;
A rotation detecting device, and
The rotation detection device is the rotation detection device according to any one of claims 3 to 7, and the phosphor layer formed on the rotation plate receives at least excitation light in the blue wavelength band and is green. A light source unit characterized in that it is a phosphor layer that emits light in the wavelength band.   9. The phosphor plate according to claim 8, wherein the rotating plate is formed with a phosphor layer that emits green wavelength band light and a phosphor layer that emits red wavelength band light upon receiving excitation light in a blue wavelength band. 10. Light source unit. A red light source device that emits light in the red wavelength band;
Blue band light diffusely transmitted through the light transmitting member attached to the rotating plate, green band light emitted from a phosphor layer formed on the rotating plate, and red band light emitted from the red light source device A light source side optical system that focuses the light onto a predetermined surface;
The light source unit according to claim 8, comprising:   The light source unit according to claim 8, a display element, a light guide optical system that guides light from the light source unit to the display element, and an image emitted from the display element. A projector comprising: a projection-side optical system that projects onto a screen; and a projector control unit that controls the light source unit and the display element.

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